www.pudn.com > mp3_source.rar > common.h

#ifndef	_COMMON_H_ 
#define	_COMMON_H_ 
 
#include  
 
/* MPEG Header Definitions - Mode Values */ 
#define	MPG_MD_STEREO           0 
#define	MPG_MD_JOINT_STEREO     1 
#define	MPG_MD_DUAL_CHANNEL     2 
#define	MPG_MD_MONO             3 
 
#define	SYNC_WORD			(long)0xfff 
#define	SYNC_WORD_LENGTH	12 
 
#define	ALIGNING			8 
 
#define	MINIMUM				4    /* Minimum size of the buffer in bytes */ 
#define	MAX_LENGTH			32	/* Maximum length of word written or read from bit stream */ 
 
#define	BINARY				0	/*Binary input file*/ 
#define	READ_MODE			0	/*Decode mode only*/ 
 
#define	FALSE				0 
#define	TRUE				1 
 
#define	MIN(A, B)			((A) < (B) ? (A) : (B)) 
 
#define	SBLIMIT				32 
#define	SSLIMIT				18 
#define	BUFFER_SIZE			4096 
#define	HAN_SIZE			512 
#define	SCALE				32768 
 
#define	PI					3.14159265358979 
#define	PI64				PI/64 
#define	PI4					PI/4 
 
/* Header Information Structure */ 
typedef struct { 
    int version; 
    int lay; 
    int error_protection; 
    int bitrate_index; 
    int sampling_frequency; 
    int padding; 
    int extension; 
    int mode; 
    int mode_ext; 
    int copyright; 
    int original; 
    int emphasis; 
} layer, *the_layer; 
 
 
/* Parent Structure Interpreting some Frame Parameters in Header */ 
typedef struct { 
    layer       *header;        /* raw header information */ 
    int         actual_mode;    /* when writing IS, may forget if 0 chs */ 
    int         stereo;         /* 1 for mono, 2 for stereo */ 
    int         jsbound;        /* first band of joint stereo coding */ 
    int         sblimit;        /* total number of sub bands */ 
} frame_params; 
 
typedef struct  bit_stream_struc { 
    FILE        *pt;            /* pointer to bit stream device */ 
    unsigned char *buf;         /* bit stream buffer */ 
    int         buf_size;       /* size of buffer (in number of bytes) */ 
    long        totbit;         /* bit counter of bit stream */ 
    int         buf_byte_idx;   /* pointer to top byte in buffer */ 
    int         buf_bit_idx;    /* pointer to top bit of top byte in buffer */ 
    int         mode;           /* bit stream open in read or write mode */ 
    int         eob;            /* end of buffer index */ 
    int         eobs;           /* end of bit stream flag */ 
    char        format; 
 
    /* format of file in rd mode (BINARY/ASCII) */ 
} Bit_stream_struc; 
 
/* Layer III side information. */ 
typedef struct { 
	unsigned main_data_begin; 
	unsigned private_bits; 
	struct { 
		unsigned scfsi[4]; 
		struct gr_info_s { 
			unsigned part2_3_length; 
			unsigned big_values; 
			unsigned global_gain; 
			unsigned scalefac_compress; 
			unsigned window_switching_flag; 
			unsigned block_type; 
			unsigned mixed_block_flag; 
			unsigned table_select[3]; 
			unsigned subblock_gain[3]; 
			unsigned region0_count; 
			unsigned region1_count; 
			unsigned preflag; 
			unsigned scalefac_scale; 
			unsigned count1table_select; 
		} gr[2]; 
	} ch[2]; 
} III_side_info_t; 
 
typedef struct { 
	int l[23];			/* [cb] */ 
	int s[3][13];		/* [window][cb] */ 
} III_scalefac_t[2];	/* [ch] */ 
 
FILE *OpenTableFile(char *name); 
 
void WriteHdr(frame_params *fr_ps); 
 
void *mem_alloc(unsigned long block, char *item); 
void alloc_buffer(Bit_stream_struc *bs, int size); 
void desalloc_buffer(Bit_stream_struc *bs); 
 
void open_bit_stream_r(Bit_stream_struc *bs, char *bs_filenam, int size); 
void close_bit_stream_r(Bit_stream_struc *bs); 
int	end_bs(Bit_stream_struc *bs); 
unsigned long sstell(Bit_stream_struc *bs); 
void refill_buffer(Bit_stream_struc *bs); 
 
unsigned int get1bit(Bit_stream_struc *bs); 
unsigned long getbits(Bit_stream_struc *bs, int N); 
int seek_sync(Bit_stream_struc *bs, unsigned long sync, int N); 
 
int js_bound(int lay, int m_ext); 
void hdr_to_frps(frame_params *fr_ps); 
 
void hputbuf(unsigned int val, int N); 
unsigned long hsstell(); 
unsigned long hgetbits(int N); 
unsigned int hget1bit(); 
void rewindNbits(int N); 
void rewindNbytes(int N); 
 
#endif	/*_COMMON_H_*/